1. Field of the Invention
The present invention relates to a method for cutting an optical lens and/or a molding die therefor.
2. Description of the Related Art
Conventionally, to cut an optical lens or a molding die therefor, a cutting blade is moved at predetermined feed pitches in a direction perpendicular to an optical axis while the optical lens and/or the molding die to be cut is rotated about the optical axis. The cut surface of the optical lens and/or the molding die, thus obtained tends to be rougher at the central portion than at the peripheral surface portion. If the surface of the central portion is rougher than the peripheral portion, the central portion must be ground by a larger amount than the peripheral portion in a grinding operation which is carried out after the cutting operation, and hence, the central portion is not completely ground when the peripheral portion has been completely ground. If the entire cut surface is uniformly ground, it takes long time to complete the grinding operation, resulting in less productivity. If the feed pitch of the cutting blade is set small, the surface roughness of the cut surface can be improved, but the time for the cutting operation is prolonged, thus leading to less productivity.